Authority concerned that the Biogen group may have pursued a strategy designed to exclude and limit competition from Sandoz, a new entrant, in the market for drugs treating multiple sclerosis containing natalizumab.

The Italian Competition Authority has launched an investigation into Biogen Italia S.r.l. and its parent company Biogen Inc. over a possible abuse of dominant position. The conduct of the two companies appears to be aimed at excluding their competitor Sandoz from offering multiple sclerosis medication containing the active ingredient natalizumab, in breach of article 102 TFEU.

Natalizumab is used to treat patients with rapidly evolving severe multiple sclerosis. For over 15 years, Biogen marketed Tysabri, the only drug (originator) containing natalizumab. Starting from 2024, following the expiry of patent protection, Sandoz attempted to market Tyruko, a biosimilar drug also containing natalizumab, equivalent to the originator, but offered at a significantly lower price. Because treatment with natalizumab may cause a rare side effect, patients are required to undergo a specific test (anti-JCV test) before starting treatment and at regular intervals thereafter, in order to assess the risk of developing PML, a serious central nervous system demyelinating disease.

In the Authority’s view, Biogen holds a dominant position in the supply of the anti-JCV test (named Stratify) because, until 2022, it was the only test authorised for screening and had effectively become the reference standard within the medical community. By leveraging its anti-JCV Stratify test, Biogen appears to be excluding and/or limiting competition from Sandoz in the market for multiple sclerosis drugs containing natalizumab. This is because Biogen makes the use of its test conditional on the purchase of its own drug and refuses to make it commercially available for patients treated with the competing biosimilar.

Moreover, these practices seem to have deprived the National Health Service of the cost advantages associated with biosimilars, since Sandoz’s drug would generate savings of at least 20% compared with Biogen’s originator.

The Authority underlines that these drugs are charged over €1,000 for a single pack, placing a significant burden on pharmaceutical expenditure, and are administered only in hospitals over long treatment cycles. The spread of biosimilars is therefore essential to promote competition, with savings that are crucial for the sustainability of the National Health Service and for funding access to the most innovative therapies for a growing number of patients. For this reason, according to the Authority, strategies that hinder and/or prevent the development of biosimilars, and competition between originators and biosimilars, may breach antitrust rules and seriously affect healthcare expenditure. Protecting competition is thus an essential part of safeguarding the right to health and access to innovative care.

Inspections at the Italian premises of Biogen were carried out yesterday by the Authority’s officials, assisted by the Special Antitrust Unit of the Italian Financial Police (Guardia di Finanza).

Rome, 27 May 2026

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